Shocker: Top Exec Leaves Hot New York Startup AppNexus Just Five Months After Joining

App Nexus CEO Brian O’KelleyLate last year, one of New York’s most valuable startups, AppNexus, made a splash with a big hire. Suddenly, that person is out.

In November, the ad tech firm brought in AOL veteran Lynda Clarizio as EVP of corporate development and operations.

Last Friday – just five months later – Clarizio and AppNexus split ways, a source close to people at the company tell us.

It’s said that Clarizio and AppNexus CEO Brian O’Kelley didn’t get along. 

O’Kelley has a very big personality, and old colleagues have told us he can sometimes be hard to work with because of it.

If Clarizio’s name rings a bell, it probably means you’ve been paying close to attention AOL over the years.

Clarizio was the second-to-last ad boss at AOL during the years before the Tim Armstrong era.

We have calls, texts and emails into AppNexus. No response yet.

AppNexus is a “real-time bidding platform.” It’s a place where ad buyers, ad sellers, and lots of middlemen like data providers and ad networks meet and move massive amounts of money and ad inventory.

With one founder, Brian O’Kelley, who made his name as CTO of a startup that sold to Yahoo for hundreds of millions of dollars, and another, Michael Rubenstein, who built Google’s ad exchange, AppNexus is considered, by some, to be “one of New York’s greatest startup success stories.”

In January, AppNexus raised $75 million. We’ve heard whispers that the valuation was just south of $1 billion.

AppNexus is a direct competitor to Google’s display advertising business, which is run by a former colleague of Rubenstein’s, Neal Mohan.

AppNexus had some trouble with executive turnover before Clarizio’s hire last fall, when SVP of product management Ari Paparo left and two other senior executives appeared close to following.

At the time of Clarizio’s hire, AppNexus CEO Brian O’Kelley said: “Lynda joins AppNexus at a time when the company is undergoing a major expansion across many dimensions including headcount and revenue, international, and product.”

“She is one of the strongest and most respected executives in the digital media universe and we are excited to have her join the team to help lead the company through this period of explosive growth. AppNexus has become the home for the digital advertising industry’s top talent, and Lynda’s addition validates that.” 

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